Here is a movie (in fast motion) showing the set up of the world record holding slot car track. It was 5,786ft 6in ( 1,763.76m ) long. This was the world record for slot car tracks in 2006 and that track worked. In 2007 the same people built an operational 2,500m long slot car track in Berlin and got the Guinness World Record for that!
I think this is cool!